Keep in mind that I am typing this on my 2011 17-inch MacBook Pro.
The 2011 17-inch MacBook Pro was in my opinion at the time an achievement coupled tightly with serious cooling deficiencies (among others) that the 2012 model was able to partially improve on.
Weaknesses? Problems? There were many with the 17-inch. Here are a partial few that many of you will be familiar with:
Significantly inadequate cooling. No SD card reader. No HDMI port. An 3/4 Express port that I have yet to take advantage of (though I understand there are many useful peripherals for it, so this may not be a weakness). Read-Write DVD drive (A plus or minus, depends). A thunderbolt port that I have yet to take advantage of. Only 4 GB of RAM standard.
For me, the cooling was the biggest issue with the machine. Heavy tasks like video editing and gaming under Windows bootcamp were constantly affected by throttling. If only they had put in a few holes in the body like they would do with the 2012 version.
So I bought the 2011 17-inch MBP with the matte screen, anti-glare, Intel 2.3 i7 2820-QM and 8 GB RAM (only stock hard drive, they did not have one with an SSD in stock at time of purchase) which despite the cooling and throttling issues for heavy work previously mentioned, performed well for most other tasks. I agree with others here in that it barely had any advantages on paper over its 15-inch sibling, but for me the 17-inch Full HD screen was the big feature. I bought it primarily for work, in the media industry. It was also my first big splash into Mac computers and OS X from a world of PCs and Microsoft Windows.
From both personal and professional standpoints, the bigger screen allowed me be much more productive while being much easier on the eyes. That is its biggest asset to me. And despite plunking down over $5K CAD on (including AppleCare and Final Cut Pro 7), the machine easily earned its keep. It's unique look alone generated countless personal and professional networking opportunities, many of which led to revenue.
I put Windows 7 on via bootcamp and then eventually Windows 10 and despite its documented relatively poor performance, I was thrilled to have the best of both worlds.
I took advantage of AppleCare to have the screen changed in 2013, as well as the motherboard as the 6700 DGPU problem began to surface. Accordingly, the screen is still pretty good today. The performance began to wane somewhere around 2014 or 2015. The battery started slowly deteriorating around that time too. It was still useable, but it was far from its years as the undisputed top of the food chain.
The GPU problem finally hit relatively later around 2017. I had to disable the DGPU and use the onboard Intel HD 3000, which means it is no longer feasible for any heavy work. One of the CPU fans is dead too.
However, this machine with a replaced battery and a Samsung 500 GB 860 EVO SSD has injected new life into its performance. I realize that this is mostly my being used to the pokey stock hard drive for so long, but the machine feels much faster and usable with a $200 investment. I will likely upgrade to 16 GB to max out its performance, but right now I am loving the value I am still getting out of this machine.
It's almost 2020, and I am typing this on my 2011 MacBook Pro with a crippled AMD HD 6750M DGPU.
Unsurprisingly, the 2011 17-inch MacBook Pro occupies a special place in my heart.